FCA US is a holding of Fiat Chrysler Automobiles N.V., and designs and manufacturers the Chrysler, Dodge, Jeep, and Ram brands. It also sells FIAT® and Alfa Romeo brands, and distributes Mopar® and Alfa Romeo parts and accessories.

The application follows EPA’s January 2017 allegation that Fiat Chrysler failed to disclose its use of engine-management software to increase emissions levels on some vehicles with 3.0-liter turbodiesel V-6 engines, including the 2014, 2015, and 2016 Jeep Grand Cherokee SUV and Dodge Ram 1500 pickups. EPA claimed that in so doing Fiat Chrysler had violated the federal Clean Air Act, although the automaker denied any violation.

Now, it stated that its new application followed “many months of close collaboration between FCA US and EPA and CARB,” and included results from extensive vehicle testing to clarify issues related to FCA US’s emissions control technology.

Once it gains EPA and CARB permission, FCA US stated it intends to install the same modified emissions software in 2014-2016 MY Jeep Grand Cherokee and Ram 1500 diesel vehicles. Owners of those vehicles would be able to receive the software updates at Jeep and Dodge Ram dealerships, and that it anticipates no effect on vehicle performance or fuel efficiency.

The automaker emphasized it believed it has addressed “the agencies’ concerns regarding the emissions software calibrations in those vehicles.”

In addition, it said the changes would resolve “ongoing discussions” with the Environment and Natural Resources Division of the U.S. Department of Justice and other governmental agencies.